Transatlantic Engineering Programs: an Experience in International Cooperation

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Plasma magnesium concentration in patients undergoing coronary artery bypass grafting

Introduction Magnesium (Mg) plays a crucial role in cell physiology and its deficiency may cause many disorders which often require intensive treatment. The aim of this study was to analyse some factors affecting preoperative plasma Mg concentration in patients undergoing coronary artery bypass grafting (CABG). Material and Methods Adult patients scheduled for elective CABG with cardio-pulmonary bypass (CPB) under general anaesthesia were studied. Plasma Mg concentration was analysed before surgery in accordance with age, domicile, profession, tobacco smoking and preoperative Mg supplementation. Blood samples were obtained from the radial artery just before the administration of anaesthesia. Results 150 patients were studied. Mean preoperative plasma Mg concentration was 0.93 ± 0.17 mmol/L; mean concentration in patients – 1.02 ± 0.16; preoperative Mg supplementation was significantly higher than in patients without such supplementation. Moreover, intellectual workers supplemented Mg more frequently and had higher plasma Mg concentration than physical workers. Plasma Mg concentration decreases in elderly patients. Patients living in cities, on average, had the highest plasma Mg concentration. Smokers had significantly lower plasma Mg concentration than non-smokers. Conclusions 1. Preoperative magnesium supplementation increases its plasma concentration. 2. Intellectual workers frequently supplement magnesium. 3. Smoking cigarettes decreases plasma magnesium concentration

Effect of hygroscopic growth on the aerosol light-scattering coefficient: A review of measurements, techniques and error sources

Knowledge of the scattering enhancement factor, f(RH), is important for an accurate description of direct aerosol radiative forcing. This factor is defined as the ratio between the scattering coefficient at enhanced relative humidity, RH, to a reference (dry) scattering coefficient. Here, we review the different experimental designs used to measure the scattering coefficient at dry and humidified conditions as well as the procedures followed to analyze the measurements. Several empirical parameterizations for the relationship between f(RH) and RH have been proposed in the literature. These parameterizations have been reviewed and tested using experimental data representative of different hygroscopic growth behavior and a new parameterization is presented. The potential sources of error in f(RH) are discussed. A Monte Carlo method is used to investigate the overall measurement uncertainty, which is found to be around 20 e40% for moderately hygroscopic aerosols. The main factors contributing to this uncertainty are the uncertainty in RH measurement, the dry reference state and the nephelometer uncertainty. A literature survey of nephelometry-based f(RH) measurements is presented as a function of aerosol type. In general, the highest f(RH) values were measured in clean marine environments, with pollution having a major influence on f(RH). Dust aerosol tended to have the lowest reported hygroscopicity of any of the aerosol types studied. Major open questions and suggestions for future research priorities are outlined.This work was supported by the Andalusia Regional Government through projects P10-RNM-6299 and P12-RNM-2409; by the Spanish Ministry of Economy and Competitiveness and FEDER through project CGL2013_45410-R; and by European Union’s Horizon 2020 research and innovation programme under grant agreement No 654109, ACTRIS-2. G. Titos was partially funded by Programa del Plan Propio de Investigación “Contrato Puente” of the University of Granada. We thank the Stockholm International Meteorological Institute (IMI) for travel support of G. Titos

Populations of planets in multiple star systems

Astronomers have discovered that both planets and binaries are abundant throughout the Galaxy. In combination, we know of over 100 planets in binary and higher-order multi-star systems, in both circumbinary and circumstellar configurations. In this chapter we review these findings and some of their implications for the formation of both stars and planets. Most of the planets found have been circumstellar, where there is seemingly a ruinous influence of the second star if sufficiently close (<50 AU). Hosts of hot Jupiters have been a particularly popular target for binary star studies, showing an enhanced rate of stellar multiplicity for moderately wide binaries (>100 AU). This was thought to be a sign of Kozai-Lidov migration, however recent studies have shown this mechanism to be too inefficient to account for the majority of hot Jupiters. A couple of dozen circumbinary planets have been proposed around both main sequence and evolved binaries. Around main sequence binaries there are preliminary indications that the frequency of gas giants is as high as those around single stars. There is however a conspicuous absence of circumbinary planets around the tightest main sequence binaries with periods of just a few days, suggesting a unique, more disruptive formation history of such close stellar pairs.Comment: Invited review chapter, accepted for publication in "Handbook of Exoplanets", ed. H. Deeg & J. A. Belmont

Europejska Unia Wspólnot Polonijnych. Kalendarium najważniejszych wydarzeń w latach 1993-2019

This article presents the calendar of the most important events related to the Union of Polish Communities in Europe (EUWP), a federation of Polish diaspora organisations from all over Europe. The EUWP was established in 1993 in London with the aim of promoting Polonia-related and Polish affairs in the process of Poland’s integration with the democratic West, cooperating with Polish communities around the world and providing assistance to Polish organisations in post-communist countries. For 28 years, the Union of Polish Communities in Europe has been involved in promoting Polish culture and integrating Polish communities, organising and taking part in various scientific and cultural events, conferences and competitions.Artykuł przedstawia kalendarium najważniejszych wydarzeń dotyczących Europejskiej Unii Wspólnot Polonijnych, federacji zrzeszającej organizacje polonijne z całej Europy. EUWP powołana została w 1993 roku w Londynie w celu promowania spraw polonijnych i polskich w integrowaniu się z demokratycznym Zachodem, współpracowania ze wspólnotami polskimi na całym świecie oraz niesienia pomocy dla organizacji polskich w państwach postkomunistycznych. Od 28 lat Europejska Unia Wspólnot Polonijnych angażuje się w promowanie kultury polskiej i integrowanie polonijnych środowisk, organizując i biorąc udział w różnego rodzaju wydarzeniach naukowych, kulturalnych, konferencjach i konkursach

PATTERN RECOGNITION BASED SHAFT ANGLE ENCODER

The aim of this paper is to present the analysis of experimentally collected data acquired from the rotating shaft. The shaft surface was sensed by the non-contacting eddy-current probe using the home made robot. The robot consists of the controlled round table for object positioning and controlled arm for sensor. Two stepper motors are employed to control the movement of the probe in two perpendicular directions. The third motor drives the table with the rotor. The stepper motors are controlled by the micro-controller programmed from the PC. Using the probe and sensing the shaft surface pattern it is possible to obtain the image of rotor surface irregularities. These irregularities are unique due to applied sensors, rotor’s material, and machining process quality. The surface irregularities can be analyzed and presented as a function of the rotor angle and/or angular velocity. The quality of the rotor surface pattern recognition is strongly influenced by the sensor characteristics and properties of the used data acquisition system. The methodology for the pertinent data analysis and possible applications are presented. Two rotor surfaces are measured in different conditions (e.g., rotations, sensor distance, etc.) and the obtained results are analyzed and compared

PATTERN RECOGNITION BASED SHAFT ANGLE ENCODER

The aim of this paper is to present the analysis of experimentally collected data acquired from the rotating shaft. The shaft surface was sensed by the non-contacting eddy-current probe using the home made robot. The robot consists of the controlled round table for object positioning and controlled arm for sensor. Two stepper motors are employed to control the movement of the probe in two perpendicular directions. The third motor drives the table with the rotor. The stepper motors are controlled by the micro-controller programmed from the PC. Using the probe and sensing the shaft surface pattern it is possible to obtain the image of rotor surface irregularities. These irregularities are unique due to applied sensors, rotor’s material, and machining process quality. The surface irregularities can be analyzed and presented as a function of the rotor angle and/or angular velocity. The quality of the rotor surface pattern recognition is strongly influenced by the sensor characteristics and properties of the used data acquisition system. The methodology for the pertinent data analysis and possible applications are presented. Two rotor surfaces are measured in different conditions (e.g., rotations, sensor distance, etc.) and the obtained results are analyzed and compared

Numerical model of the axial magnetic bearing with six cylindrical poles

The paper presents a numerical model of the novel design of the axial magnetic bearing with six cylindrical poles. The motivation behind this idea was to eliminate vibra- tions in rotating machinery due to the axial load. Common conception of such a bearing provides a single component of the electromagnetic force, which is not enough to reduce transverse and lateral vibrations of the armature. The proposed design allows for avoiding wobbling of the disc with the use of a few axial force components that are able to actively compensate the axial load and stabilise the disc in a balanced position. Before a real device is manufactured, a virtual prototype should be prepared. The accurate numerical model will provide essential knowledge about the performance of the axial magnetic bearing